import os
import socket
from subprocess import Popen, PIPE
from contextlib import contextmanager
import numpy as np
from ase.calculators.calculator import (Calculator, all_changes,
PropertyNotImplementedError)
import ase.units as units
from ase.utils import IOContext
from ase.stress import full_3x3_to_voigt_6_stress
def actualunixsocketname(name):
return '/tmp/ipi_{}'.format(name)
class SocketClosed(OSError):
pass
class IPIProtocol:
"""Communication using IPI protocol."""
def __init__(self, socket, txt=None):
self.socket = socket
if txt is None:
def log(*args):
pass
else:
def log(*args):
print('Driver:', *args, file=txt)
txt.flush()
self.log = log
def sendmsg(self, msg):
self.log(' sendmsg', repr(msg))
# assert msg in self.statements, msg
msg = msg.encode('ascii').ljust(12)
self.socket.sendall(msg)
def _recvall(self, nbytes):
"""Repeatedly read chunks until we have nbytes.
Normally we get all bytes in one read, but that is not guaranteed."""
remaining = nbytes
chunks = []
while remaining > 0:
chunk = self.socket.recv(remaining)
if len(chunk) == 0:
# (If socket is still open, recv returns at least one byte)
raise SocketClosed()
chunks.append(chunk)
remaining -= len(chunk)
msg = b''.join(chunks)
assert len(msg) == nbytes and remaining == 0
return msg
def recvmsg(self):
msg = self._recvall(12)
if not msg:
raise SocketClosed()
assert len(msg) == 12, msg
msg = msg.rstrip().decode('ascii')
# assert msg in self.responses, msg
self.log(' recvmsg', repr(msg))
return msg
def send(self, a, dtype):
buf = np.asarray(a, dtype).tobytes()
# self.log(' send {}'.format(np.array(a).ravel().tolist()))
self.log(' send {} bytes of {}'.format(len(buf), dtype))
self.socket.sendall(buf)
def recv(self, shape, dtype):
a = np.empty(shape, dtype)
nbytes = np.dtype(dtype).itemsize * np.prod(shape)
buf = self._recvall(nbytes)
assert len(buf) == nbytes, (len(buf), nbytes)
self.log(' recv {} bytes of {}'.format(len(buf), dtype))
# print(np.frombuffer(buf, dtype=dtype))
a.flat[:] = np.frombuffer(buf, dtype=dtype)
# self.log(' recv {}'.format(a.ravel().tolist()))
assert np.isfinite(a).all()
return a
def sendposdata(self, cell, icell, positions):
assert cell.size == 9
assert icell.size == 9
assert positions.size % 3 == 0
self.log(' sendposdata')
self.sendmsg('POSDATA')
self.send(cell.T / units.Bohr, np.float64)
self.send(icell.T * units.Bohr, np.float64)
self.send(len(positions), np.int32)
self.send(positions / units.Bohr, np.float64)
def recvposdata(self):
cell = self.recv((3, 3), np.float64).T.copy()
icell = self.recv((3, 3), np.float64).T.copy()
natoms = self.recv(1, np.int32)
natoms = int(natoms)
positions = self.recv((natoms, 3), np.float64)
return cell * units.Bohr, icell / units.Bohr, positions * units.Bohr
def sendrecv_force(self):
self.log(' sendrecv_force')
self.sendmsg('GETFORCE')
msg = self.recvmsg()
assert msg == 'FORCEREADY', msg
e = self.recv(1, np.float64)[0]
natoms = self.recv(1, np.int32)
assert natoms >= 0
forces = self.recv((int(natoms), 3), np.float64)
virial = self.recv((3, 3), np.float64).T.copy()
nmorebytes = self.recv(1, np.int32)
nmorebytes = int(nmorebytes)
if nmorebytes > 0:
# Receiving 0 bytes will block forever on python2.
morebytes = self.recv(nmorebytes, np.byte)
else:
morebytes = b''
return (e * units.Ha, (units.Ha / units.Bohr) * forces,
units.Ha * virial, morebytes)
def sendforce(self, energy, forces, virial,
morebytes=np.zeros(1, dtype=np.byte)):
assert np.array([energy]).size == 1
assert forces.shape[1] == 3
assert virial.shape == (3, 3)
self.log(' sendforce')
self.sendmsg('FORCEREADY') # mind the units
self.send(np.array([energy / units.Ha]), np.float64)
natoms = len(forces)
self.send(np.array([natoms]), np.int32)
self.send(units.Bohr / units.Ha * forces, np.float64)
self.send(1.0 / units.Ha * virial.T, np.float64)
# We prefer to always send at least one byte due to trouble with
# empty messages. Reading a closed socket yields 0 bytes
# and thus can be confused with a 0-length bytestring.
self.send(np.array([len(morebytes)]), np.int32)
self.send(morebytes, np.byte)
def status(self):
self.log(' status')
self.sendmsg('STATUS')
msg = self.recvmsg()
return msg
def end(self):
self.log(' end')
self.sendmsg('EXIT')
def recvinit(self):
self.log(' recvinit')
bead_index = self.recv(1, np.int32)
nbytes = self.recv(1, np.int32)
initbytes = self.recv(nbytes, np.byte)
return bead_index, initbytes
def sendinit(self):
# XXX Not sure what this function is supposed to send.
# It 'works' with QE, but for now we try not to call it.
self.log(' sendinit')
self.sendmsg('INIT')
self.send(0, np.int32) # 'bead index' always zero for now
# We send one byte, which is zero, since things may not work
# with 0 bytes. Apparently implementations ignore the
# initialization string anyway.
self.send(1, np.int32)
self.send(np.zeros(1), np.byte) # initialization string
def calculate(self, positions, cell):
self.log('calculate')
msg = self.status()
# We don't know how NEEDINIT is supposed to work, but some codes
# seem to be okay if we skip it and send the positions instead.
if msg == 'NEEDINIT':
self.sendinit()
msg = self.status()
assert msg == 'READY', msg
icell = np.linalg.pinv(cell).transpose()
self.sendposdata(cell, icell, positions)
msg = self.status()
assert msg == 'HAVEDATA', msg
e, forces, virial, morebytes = self.sendrecv_force()
r = dict(energy=e,
forces=forces,
virial=virial)
if morebytes:
r['morebytes'] = morebytes
return r
@contextmanager
def bind_unixsocket(socketfile):
assert socketfile.startswith('/tmp/ipi_'), socketfile
serversocket = socket.socket(socket.AF_UNIX)
try:
serversocket.bind(socketfile)
except OSError as err:
raise OSError('{}: {}'.format(err, repr(socketfile)))
try:
with serversocket:
yield serversocket
finally:
os.unlink(socketfile)
@contextmanager
def bind_inetsocket(port):
serversocket = socket.socket(socket.AF_INET)
serversocket.setsockopt(socket.SOL_SOCKET,
socket.SO_REUSEADDR, 1)
serversocket.bind(('', port))
with serversocket:
yield serversocket
class FileIOSocketClientLauncher:
def __init__(self, calc):
self.calc = calc
def __call__(self, atoms, properties=None, port=None, unixsocket=None):
assert self.calc is not None
cmd = self.calc.command.replace('PREFIX', self.calc.prefix)
self.calc.write_input(atoms, properties=properties,
system_changes=all_changes)
cwd = self.calc.directory
cmd = cmd.format(port=port, unixsocket=unixsocket)
return Popen(cmd, shell=True, cwd=cwd)
[docs]class SocketServer(IOContext):
default_port = 31415
def __init__(self, # launch_client=None,
port=None, unixsocket=None, timeout=None,
log=None):
"""Create server and listen for connections.
Parameters:
client_command: Shell command to launch client process, or None
The process will be launched immediately, if given.
Else the user is expected to launch a client whose connection
the server will then accept at any time.
One calculate() is called, the server will block to wait
for the client.
port: integer or None
Port on which to listen for INET connections. Defaults
to 31415 if neither this nor unixsocket is specified.
unixsocket: string or None
Filename for unix socket.
timeout: float or None
timeout in seconds, or unlimited by default.
This parameter is passed to the Python socket object; see
documentation therof
log: file object or None
useful debug messages are written to this."""
if unixsocket is None and port is None:
port = self.default_port
elif unixsocket is not None and port is not None:
raise ValueError('Specify only one of unixsocket and port')
self.port = port
self.unixsocket = unixsocket
self.timeout = timeout
self._closed = False
if unixsocket is not None:
actualsocket = actualunixsocketname(unixsocket)
conn_name = 'UNIX-socket {}'.format(actualsocket)
socket_context = bind_unixsocket(actualsocket)
else:
conn_name = 'INET port {}'.format(port)
socket_context = bind_inetsocket(port)
self.serversocket = self.closelater(socket_context)
if log:
print('Accepting clients on {}'.format(conn_name), file=log)
self.serversocket.settimeout(timeout)
self.serversocket.listen(1)
self.log = log
self.proc = None
self.protocol = None
self.clientsocket = None
self.address = None
#if launch_client is not None:
# self.proc = launch_client(port=port, unixsocket=unixsocket)
def _accept(self):
"""Wait for client and establish connection."""
# It should perhaps be possible for process to be launched by user
log = self.log
if log:
print('Awaiting client', file=self.log)
# If we launched the subprocess, the process may crash.
# We want to detect this, using loop with timeouts, and
# raise an error rather than blocking forever.
if self.proc is not None:
self.serversocket.settimeout(1.0)
while True:
try:
self.clientsocket, self.address = self.serversocket.accept()
self.closelater(self.clientsocket)
except socket.timeout:
if self.proc is not None:
status = self.proc.poll()
if status is not None:
raise OSError('Subprocess terminated unexpectedly'
' with status {}'.format(status))
else:
break
self.serversocket.settimeout(self.timeout)
self.clientsocket.settimeout(self.timeout)
if log:
# For unix sockets, address is b''.
source = ('client' if self.address == b'' else self.address)
print('Accepted connection from {}'.format(source), file=log)
self.protocol = IPIProtocol(self.clientsocket, txt=log)
def close(self):
if self._closed:
return
super().close()
if self.log:
print('Close socket server', file=self.log)
self._closed = True
# Proper way to close sockets?
# And indeed i-pi connections...
# if self.protocol is not None:
# self.protocol.end() # Send end-of-communication string
self.protocol = None
if self.proc is not None:
exitcode = self.proc.wait()
if exitcode != 0:
import warnings
# Quantum Espresso seems to always exit with status 128,
# even if successful.
# Should investigate at some point
warnings.warn('Subprocess exited with status {}'
.format(exitcode))
# self.log('IPI server closed')
def calculate(self, atoms):
"""Send geometry to client and return calculated things as dict.
This will block until client has established connection, then
wait for the client to finish the calculation."""
assert not self._closed
# If we have not established connection yet, we must block
# until the client catches up:
if self.protocol is None:
self._accept()
return self.protocol.calculate(atoms.positions, atoms.cell)
[docs]class SocketClient:
def __init__(self, host='localhost', port=None,
unixsocket=None, timeout=None, log=None, comm=None):
"""Create client and connect to server.
Parameters:
host: string
Hostname of server. Defaults to localhost
port: integer or None
Port to which to connect. By default 31415.
unixsocket: string or None
If specified, use corresponding UNIX socket.
See documentation of unixsocket for SocketIOCalculator.
timeout: float or None
See documentation of timeout for SocketIOCalculator.
log: file object or None
Log events to this file
comm: communicator or None
MPI communicator object. Defaults to ase.parallel.world.
When ASE runs in parallel, only the process with world.rank == 0
will communicate over the socket. The received information
will then be broadcast on the communicator. The SocketClient
must be created on all ranks of world, and will see the same
Atoms objects."""
if comm is None:
from ase.parallel import world
comm = world
# Only rank0 actually does the socket work.
# The other ranks only need to follow.
#
# Note: We actually refrain from assigning all the
# socket-related things except on master
self.comm = comm
if self.comm.rank == 0:
if unixsocket is not None:
sock = socket.socket(socket.AF_UNIX)
actualsocket = actualunixsocketname(unixsocket)
sock.connect(actualsocket)
else:
if port is None:
port = SocketServer.default_port
sock = socket.socket(socket.AF_INET)
sock.connect((host, port))
sock.settimeout(timeout)
self.host = host
self.port = port
self.unixsocket = unixsocket
self.protocol = IPIProtocol(sock, txt=log)
self.log = self.protocol.log
self.closed = False
self.bead_index = 0
self.bead_initbytes = b''
self.state = 'READY'
def close(self):
if not self.closed:
self.log('Close SocketClient')
self.closed = True
self.protocol.socket.close()
def calculate(self, atoms, use_stress):
# We should also broadcast the bead index, once we support doing
# multiple beads.
self.comm.broadcast(atoms.positions, 0)
self.comm.broadcast(np.ascontiguousarray(atoms.cell), 0)
energy = atoms.get_potential_energy()
forces = atoms.get_forces()
if use_stress:
stress = atoms.get_stress(voigt=False)
virial = -atoms.get_volume() * stress
else:
virial = np.zeros((3, 3))
return energy, forces, virial
def irun(self, atoms, use_stress=None):
if use_stress is None:
use_stress = any(atoms.pbc)
my_irun = self.irun_rank0 if self.comm.rank == 0 else self.irun_rankN
return my_irun(atoms, use_stress)
def irun_rankN(self, atoms, use_stress=True):
stop_criterion = np.zeros(1, bool)
while True:
self.comm.broadcast(stop_criterion, 0)
if stop_criterion[0]:
return
self.calculate(atoms, use_stress)
yield
def irun_rank0(self, atoms, use_stress=True):
# For every step we either calculate or quit. We need to
# tell other MPI processes (if this is MPI-parallel) whether they
# should calculate or quit.
try:
while True:
try:
msg = self.protocol.recvmsg()
except SocketClosed:
# Server closed the connection, but we want to
# exit gracefully anyway
msg = 'EXIT'
if msg == 'EXIT':
# Send stop signal to clients:
self.comm.broadcast(np.ones(1, bool), 0)
# (When otherwise exiting, things crashed and we should
# let MPI_ABORT take care of the mess instead of trying
# to synchronize the exit)
return
elif msg == 'STATUS':
self.protocol.sendmsg(self.state)
elif msg == 'POSDATA':
assert self.state == 'READY'
cell, icell, positions = self.protocol.recvposdata()
atoms.cell[:] = cell
atoms.positions[:] = positions
# User may wish to do something with the atoms object now.
# Should we provide option to yield here?
#
# (In that case we should MPI-synchronize *before*
# whereas now we do it after.)
# Send signal for other ranks to proceed with calculation:
self.comm.broadcast(np.zeros(1, bool), 0)
energy, forces, virial = self.calculate(atoms, use_stress)
self.state = 'HAVEDATA'
yield
elif msg == 'GETFORCE':
assert self.state == 'HAVEDATA', self.state
self.protocol.sendforce(energy, forces, virial)
self.state = 'NEEDINIT'
elif msg == 'INIT':
assert self.state == 'NEEDINIT'
bead_index, initbytes = self.protocol.recvinit()
self.bead_index = bead_index
self.bead_initbytes = initbytes
self.state = 'READY'
else:
raise KeyError('Bad message', msg)
finally:
self.close()
def run(self, atoms, use_stress=False):
for _ in self.irun(atoms, use_stress=use_stress):
pass
[docs]class SocketIOCalculator(Calculator, IOContext):
implemented_properties = ['energy', 'free_energy', 'forces', 'stress']
supported_changes = {'positions', 'cell'}
def __init__(self, calc=None, port=None,
unixsocket=None, timeout=None, log=None, *,
launch_client=None):
"""Initialize socket I/O calculator.
This calculator launches a server which passes atomic
coordinates and unit cells to an external code via a socket,
and receives energy, forces, and stress in return.
ASE integrates this with the Quantum Espresso, FHI-aims and
Siesta calculators. This works with any external code that
supports running as a client over the i-PI protocol.
Parameters:
calc: calculator or None
If calc is not None, a client process will be launched
using calc.command, and the input file will be generated
using ``calc.write_input()``. Otherwise only the server will
run, and it is up to the user to launch a compliant client
process.
port: integer
port number for socket. Should normally be between 1025
and 65535. Typical ports for are 31415 (default) or 3141.
unixsocket: str or None
if not None, ignore host and port, creating instead a
unix socket using this name prefixed with ``/tmp/ipi_``.
The socket is deleted when the calculator is closed.
timeout: float >= 0 or None
timeout for connection, by default infinite. See
documentation of Python sockets. For longer jobs it is
recommended to set a timeout in case of undetected
client-side failure.
log: file object or None (default)
logfile for communication over socket. For debugging or
the curious.
In order to correctly close the sockets, it is
recommended to use this class within a with-block:
>>> with SocketIOCalculator(...) as calc:
... atoms.calc = calc
... atoms.get_forces()
... atoms.rattle()
... atoms.get_forces()
It is also possible to call calc.close() after
use. This is best done in a finally-block."""
Calculator.__init__(self)
if calc is not None:
if launch_client is not None:
raise ValueError('Cannot pass both calc and launch_client')
launch_client = FileIOSocketClientLauncher(calc)
self.launch_client = launch_client
#self.calc = calc
self.timeout = timeout
self.server = None
self.log = self.openfile(log)
# We only hold these so we can pass them on to the server.
# They may both be None as stored here.
self._port = port
self._unixsocket = unixsocket
# If there is a calculator, we will launch in calculate() because
# we are responsible for executing the external process, too, and
# should do so before blocking. Without a calculator we want to
# block immediately:
if self.launch_client is None:
self.server = self.launch_server()
def todict(self):
d = {'type': 'calculator',
'name': 'socket-driver'}
#if self.calc is not None:
# d['calc'] = self.calc.todict()
return d
def launch_server(self):
return self.closelater(SocketServer(
#launch_client=launch_client,
port=self._port,
unixsocket=self._unixsocket,
timeout=self.timeout, log=self.log,
))
def calculate(self, atoms=None, properties=['energy'],
system_changes=all_changes):
bad = [change for change in system_changes
if change not in self.supported_changes]
# First time calculate() is called, system_changes will be
# all_changes. After that, only positions and cell may change.
if self.atoms is not None and any(bad):
raise PropertyNotImplementedError(
'Cannot change {} through IPI protocol. '
'Please create new socket calculator.'
.format(bad if len(bad) > 1 else bad[0]))
self.atoms = atoms.copy()
if self.server is None:
self.server = self.launch_server()
proc = self.launch_client(atoms, properties,
port=self._port,
unixsocket=self._unixsocket)
self.server.proc = proc # XXX nasty hack
results = self.server.calculate(atoms)
results['free_energy'] = results['energy']
virial = results.pop('virial')
if self.atoms.cell.rank == 3 and any(self.atoms.pbc):
vol = atoms.get_volume()
results['stress'] = -full_3x3_to_voigt_6_stress(virial) / vol
self.results.update(results)
def close(self):
self.server = None
super().close()
class PySocketIOClient:
def __init__(self, calculator_factory):
self._calculator_factory = calculator_factory
def __call__(self, atoms, properties=None, port=None, unixsocket=None):
import sys
import pickle
# We pickle everything first, so we won't need to bother with the
# process as long as it succeeds.
transferbytes = pickle.dumps([
dict(unixsocket=unixsocket, port=port),
atoms.copy(),
self._calculator_factory,
])
proc = Popen([sys.executable, '-m', 'ase.calculators.socketio'],
stdin=PIPE)
proc.stdin.write(transferbytes)
proc.stdin.close()
return proc
@staticmethod
def main():
import sys
import pickle
socketinfo, atoms, get_calculator = pickle.load(sys.stdin.buffer)
atoms.calc = get_calculator()
client = SocketClient(host='localhost',
unixsocket=socketinfo.get('unixsocket'),
port=socketinfo.get('port'))
# XXX In principle we could avoid calculating stress until
# someone requests the stress, could we not?
# Which would make use_stress boolean unnecessary.
client.run(atoms, use_stress=True)
if __name__ == '__main__':
PySocketIOClient.main()